You don't get vendor lock in if you're able to run GHA on any compute you'd like (yes, I'm aware of self-hosted runners, and even that their Packer code is open

You don't get vendor lock in if you're able to run GHA on any compute you'd like (yes, I'm aware of self-hosted runners, and even that their Packer code is open source. That doesn't make it easy to use GHA outside of github.com)